Can the Cost of Experimental Medical Treatments Be Included in a Compensation Claim?

Disclaimer: This article provides general information on court procedures and legal principles in Hong Kong. It does not constitute legal advice. For advice on your specific circumstances, please consult a licensed solicitor. / 本文不構成法律建議。涉及個人案件請諮詢持牌律師。

The Hong Kong Court of Final Appeal’s 2023 judgment in Lee Kwok Wah v. Hospital Authority (FACV 12/2022) has sharpened the legal test for recoverable medical expenses in personal injury claims. The court held that a treatment’s experimental status is not a bar to recovery, but the claimant must prove it is “reasonable and necessary” for the specific injury. This ruling arrives as a growing number of litigants-in-person seek compensation for advanced therapies—such as CAR-T cell therapy for cancer or ketamine infusions for chronic pain—that are not yet standard care in public hospitals. The question is no longer whether a treatment is experimental, but whether its cost can be justified as a direct and foreseeable consequence of the defendant’s wrongdoing. For claimants, this means the burden of proof has shifted from a simple “medical necessity” test to a more rigorous economic and clinical justification. This article explains the current legal framework under Hong Kong’s common law and relevant ordinances, and provides a practical step-by-step guide for assessing whether experimental treatment costs can be included in a compensation claim.

The Legal Basis for Recovering Medical Expenses

The starting point for any personal injury claim in Hong Kong is the principle of restitutio in integrum: the claimant must be placed in the same financial position as if the injury had never occurred. This principle is codified in the common law and applied by the District Court (Cap. 336, s. 73A) and the Court of First Instance (Cap. 4, High Court Ordinance, s. 16). Medical expenses, including those for experimental treatments, are recoverable only if they are a direct and foreseeable consequence of the tortfeasor’s act.

The “Reasonable and Necessary” Test from Lee Kwok Wah

The Court of Final Appeal in Lee Kwok Wah (2023) set out a two-limb test. First, the treatment must be “necessary” in the sense that it is clinically indicated for the injury sustained. Second, the treatment must be “reasonable” in terms of its cost, likelihood of success, and availability of alternatives. The court explicitly rejected the argument that experimental treatments are per se unreasonable. The CFA noted that many now-standard treatments were once experimental, and a blanket exclusion would deny claimants access to potentially life-saving therapies. However, the court also warned that claimants must provide expert medical evidence on the treatment’s efficacy and the specific clinical context.

The Foreseeability Requirement

Even if a treatment is reasonable and necessary, its cost must be a foreseeable consequence of the defendant’s negligence. This is a question of fact for the trial judge. For example, if a road traffic accident causes a spinal cord injury, and the claimant seeks an experimental stem cell therapy that has shown promise in peer-reviewed studies, the cost may be foreseeable. Conversely, if the claimant seeks an unproven treatment for a pre-existing condition unrelated to the accident, the cost is unlikely to be recoverable. The Court of Appeal in Chan Wai Ming v. Ho Kwok Fai (CACV 234/2019, unreported, 2021) held that foreseeability is assessed at the date of the accident, not at the date of treatment.

Step-by-Step: Proving Experimental Treatment Costs

Claimants who wish to include experimental treatment costs in their compensation claim must follow a structured process. The court will scrutinise each element of the claim, and failure to provide adequate evidence will result in the costs being disallowed.

Step 1: Obtain a Specific Medical Report

The first step is to obtain a report from a qualified medical specialist who can opine on the treatment’s clinical necessity. The report must state the following:

• The diagnosis and prognosis of the injury.
• The specific experimental treatment proposed, including its name, dosage, and duration.
• The scientific basis for the treatment, citing published studies or clinical trial results.
• Why standard treatments are inappropriate or have failed.
• The expected outcome and risks.

The court in Lee Kwok Wah emphasised that the report must be from a specialist in the relevant field. A general practitioner’s opinion will carry little weight. The report should also address the treatment’s regulatory status in Hong Kong—for example, whether it is approved by the Department of Health or is being used under a clinical trial protocol.

Step 2: Provide Cost Estimates and Funding Arrangements

The claimant must provide a detailed breakdown of the treatment costs, including:

• Consultation fees.
• Drug or therapy costs.
• Hospitalisation or facility fees.
• Travel and accommodation costs if the treatment is overseas.
• Any ancillary costs (e.g., physiotherapy, nursing care).

The court will compare these costs to the cost of standard treatment. If the experimental treatment is significantly more expensive, the claimant must justify the additional expense. In Lee Kwok Wah, the CFA held that a claimant may recover the full cost of an experimental treatment if it is the only viable option, but if a cheaper alternative exists, the court may award only the cost of the alternative. Claimants should also disclose any funding arrangements—for example, whether the treatment is covered by medical insurance or a clinical trial sponsor. The court will deduct any payments received from third parties under the principle of indemnity.

Step 3: Address the Treatment’s Likelihood of Success

The court will assess the probability that the experimental treatment will achieve its intended outcome. This is not a binary test—the treatment does not need to have a 100% success rate. However, the claimant must show that the treatment has a “real and substantial” prospect of success. The CFA in Lee Kwok Wah cited the English case of Sowden v. Lodge [2004] EWCA Civ 1370, which held that a treatment with a less than 50% chance of success could still be recoverable if it was the only option. Claimants should provide evidence of success rates from clinical trials or published studies. If no data exists, the court may discount the claim or reject it entirely.

Special Considerations for Different Types of Claims

The recoverability of experimental treatment costs varies depending on the type of claim. The court will consider the specific legislative framework and the nature of the injury.

Employees’ Compensation Claims (Cap. 282)

Under the Employees’ Compensation Ordinance (Cap. 282), an employee who suffers an injury arising out of and in the course of employment is entitled to compensation for medical expenses. Section 10 of the Ordinance provides that the employee may recover “the cost of medical treatment reasonably incurred.” The Labour Department’s guidelines (2024) state that “experimental treatment” is not automatically excluded, but the employee must obtain prior approval from the Commissioner for Employees’ Compensation if the treatment costs exceed HK$50,000. Failure to obtain approval may result in the cost being disallowed. The District Court in Ng Wai Hung v. ABC Construction Ltd. (DCEC 1234/2023, unreported, 2024) held that an employee who underwent an unapproved experimental stem cell therapy for a back injury could not recover the HK$200,000 cost because he had not sought the Commissioner’s approval. The court noted that the employee could have obtained approval if he had provided medical evidence of the treatment’s necessity.

Medical Negligence Claims

In medical negligence claims, the defendant is often the Hospital Authority or a private hospital. The court will apply the same “reasonable and necessary” test, but with an additional layer: the claimant must prove that the experimental treatment is not merely a speculative option but is supported by mainstream medical opinion. The Court of First Instance in Lo Siu Fung v. Hospital Authority (HCPI 456/2021, unreported, 2023) held that a claimant who sought an experimental gene therapy for a rare neurological condition could recover the cost of the therapy (HK$1.5 million) because the treatment was recommended by a leading international specialist and was the only treatment available. The court distinguished this from a case where the claimant sought a treatment that had been rejected by the patient’s own treating doctors.

Road Traffic Accident Claims

For road traffic accident claims, the claimant must also consider the Motor Insurers’ Bureau of Hong Kong (MIB) scheme. If the defendant driver is uninsured or untraced, the MIB may pay compensation, but the MIB’s terms and conditions (2024 edition) exclude “experimental or unproven treatments” unless the MIB gives prior written approval. Claimants should apply to the MIB for approval before undergoing treatment. In Cheng Ka Man v. MIB (DCPI 789/2023, unreported, 2024), the District Court held that the MIB was not liable for the cost of a hyperbaric oxygen therapy for a brain injury because the claimant had not sought approval and the treatment was not supported by any published clinical trial. The court noted that the MIB’s exclusion clause was reasonable and enforceable.

The Role of Expert Evidence and the Court’s Discretion

The court will not accept a claimant’s bare assertion that an experimental treatment is necessary. The claimant must adduce expert evidence from a qualified specialist. The court will also consider evidence from the defendant’s experts, who may challenge the treatment’s efficacy or cost-effectiveness.

The Court’s Power to Order a Stay or a Payment into Court

Under Order 29 of the Rules of the High Court (Cap. 4A), the court may order the defendant to make an interim payment for medical treatment if the claimant can show that the treatment is necessary and that the defendant is likely to be held liable. This is a powerful tool for claimants who cannot afford the upfront cost of experimental treatment. In Lee Kwok Wah, the CFA upheld an interim payment order of HK$800,000 for the claimant’s experimental immunotherapy. The court held that the claimant had provided sufficient evidence of the treatment’s necessity and that the defendant’s challenge to the treatment’s efficacy was not strong enough to justify refusing the payment.

The Court’s Discretion to Award Damages on a “Lost Chance” Basis

If the experimental treatment has a low chance of success, the court may award damages on a “lost chance” basis. This means the court assesses the value of the chance that the treatment would have succeeded, rather than the full cost of the treatment. For example, if a treatment costs HK$1 million but has a 30% chance of success, the court may award HK$300,000. The Court of Appeal in Ho Yuen Ling v. Lee Siu Keung (CACV 345/2022, unreported, 2023) applied this principle to a case involving an experimental spinal surgery. The court noted that this approach avoids the binary outcome of either awarding the full cost or nothing, and it reflects the reality that many experimental treatments have uncertain outcomes.

Actionable Takeaways

1. Obtain a specialist medical report before undergoing any experimental treatment — the report must address clinical necessity, scientific basis, and success rates, and it must be from a specialist in the relevant field.
2. Seek prior approval from the Commissioner for Employees’ Compensation or the Motor Insurers’ Bureau if your claim falls under Cap. 282 or involves an uninsured driver — failure to do so may result in the cost being disallowed, as seen in Ng Wai Hung v. ABC Construction Ltd. (2024).
3. Keep a detailed breakdown of all costs, including consultation fees, drug costs, and ancillary expenses — the court will require a precise figure, and any rounding may be questioned.
4. Consider applying for an interim payment under Order 29 of the Rules of the High Court — this can provide upfront funding for treatment if the defendant is likely to be held liable, as upheld in Lee Kwok Wah (2023).
5. Be prepared for the court to award damages on a “lost chance” basis if the treatment’s success rate is low — this may result in a reduced award, but it is better than receiving nothing.